Vacuum prosthesis with force sensing member

ABSTRACT

A prosthetic device includes a socket assembly defining a cavity and configured to receive a portion of a residual limb of a user within the cavity, a force sensing member configured to detect forces applied to the residual limb at a plurality of locations about the portion of the residual limb and generate signals based on the detected force, a vacuum system in fluid communication with the socket and configured to control an amount of vacuum applied to the cavity, and a controller coupled to the force sensing member and the vacuum system. The controller is configured to receive the signals from the force sensing member and control operation of the vacuum system during use of the prosthetic device by the user based at least in part on the signals received from the force sensing member.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The present application claims the benefit of U.S. ProvisionalApplication No. 61/418,724, filed Dec. 1, 2010, which is incorporated byreference herein in its entirety. The present application is related toInternational Patent Application No. PCT/US2009/046497, filed Jun. 5,2009, published as International Publication No. WO2009/149412, which isincorporated by reference herein in its entirety.

BACKGROUND

The present disclosure relates generally to the field of prostheticdevices, and more specifically, to methods and systems related to vacuumprosthetic devices having force sensing features.

Prosthetic devices such as lower limb prosthetics often include a sockethaving an inner cavity that receives a portion of a residual limb of auser. A vacuum system may be used to create a vacuum within the spacebetween the inner cavity of the socket and the residual limb.

There are many challenges associated with maintaining a proper vacuumlevel in a prosthetic device in order to, for example, ensure properoperation of the prosthetic device and provide a comfortable fit forusers of such devices. As such, it would be desirable to provide animproved prosthetic device that addresses these challenges.

SUMMARY

One embodiment relates to a prosthetic device comprising a socketassembly defining a cavity and configured to receive a portion of aresidual limb of a user within the cavity; a force sensing memberconfigured to detect forces applied to the residual limb at a pluralityof locations about the portion of the residual limb and generate signalsbased on the detected force; a vacuum system in fluid communication withthe socket and configured to control an amount of vacuum applied to thecavity; and a controller coupled to the force sensing member and thevacuum system, the controller configured to receive the signals from theforce sensing member and control operation of the vacuum system duringuse of the prosthetic device by the user based at least in part on thesignals received from the force sensing member.

Another embodiment relates to a method comprising applying an amount ofvacuum to a cavity defined by a socket and a portion of a residual limbof a user, the portion of the residual limb received within the socket;detecting forces experienced by the residual limb at a plurality oflocations about the portion of the residual limb during use of theprosthetic device by the user; providing signals to a controller basedon the forces detected at the plurality of locations; and controllingthe amount of vacuum applied to the cavity based on the signals.

Another embodiment relates to a method comprising detecting forcesexperienced by a residual limb at a plurality of locations about aportion of the residual limb during use of a prosthetic device;providing signals to a controller based on the forces detected at theplurality of locations; and selectively controlling an amount of vacuumapplied to each of a plurality of localized regions on the residual limbbased on the signals.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thefollowing detailed description, taken in conjunction with theaccompanying drawings, wherein like reference numerals refer to likeelements.

FIG. 1 is a perspective view of a prosthetic device fitted to residuallimb of a user according to an exemplary embodiment.

FIG. 2 is a partial cross-sectional view of the prosthetic device ofclaim 1 according to an exemplary embodiment.

FIG. 3 is a schematic block diagram of a control system of theprosthetic device of FIG. 1 according to an exemplary embodiment.

FIG. 4 is a perspective view of a force sensing member of the prostheticdevice of FIG. 1 according to an exemplary embodiment.

FIG. 5 is a is a perspective view of a force distribution graphillustrating the force distribution about a force sensing memberaccording to an exemplary embodiment.

FIG. 6 is a flowchart illustrating a method of controlling a vacuumlevel of the prosthetic device of FIG. 1 according to an exemplaryembodiment.

FIG. 7 is a flowchart illustrating a method of controlling a vacuumlevel of the prosthetic device of FIG. 1 according to an exemplaryembodiment.

FIG. 8 is a perspective view of a force sensing member according to anexemplary embodiment.

FIG. 9 is a perspective view of a force sensing member according to anexemplary embodiment.

FIG. 10 is a partially cutaway perspective view of a socket assembly ofthe prosthetic device of FIG. 1 according to another exemplaryembodiment.

FIG. 11 is a partial cross section view of a portion of the socketassembly of FIG. 10 according to an exemplary embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Referring generally to the FIGURES, various embodiments of prostheticdevices are shown according to exemplary embodiments. Though variousembodiments herein are described in the context of an artificial leg, itis contemplated that the present disclosure is equally applicable toother contexts in which a device is connected to a user's body. Forexample, the device could be an artificial arm, an orthotic component,or other prosthetic/orthotic products that use vacuum or similar methodsto connect to a user. The connection method need not be a fullyencompassing socket like a prosthesis. Further, a vacuum could assist aconnection device or may be used as a stabilizer in connection withvarious connection methods.

Referring to FIG. 1, a prosthetic device 10 is shown according to anexemplary embodiment. Device 10 includes a socket assembly 12, a pylon14, an artificial foot 16, and a control system 18. Device 10 isintended to restore functionality to patients having lost limbs such aslegs, arms, and the like. Generally, socket assembly 12 receives aportion of a residual limb of a user. Pylon 14 is a mechanical structurethat provides a mechanical support and interface between socket assembly12 and artificial foot 16. Artificial foot 16 may be designed toreplicate a real foot (or, similarly, a hand, etc., depending on theparticular application). As described in greater detail below, controlsystem 18 controls an amount of vacuum applied to the socket assembly12, where the vacuum provides a negative pressure to maintain theresidual limb securely in place within the socket assembly. Based onvarious factors, control system 18 may vary the vacuum applied to socketassembly 12 to optimize the performance of device 10 for users.

Referring to FIGS. 1-2, according to one embodiment, a residual limb ofa user is received within an inner liner 20. Inner liner 20 may beconfigured to fit around the residual limb and into outer casing 22. Insome embodiments, inner liner may be formed of conventional linermaterial. The particular size and/or shape of inner liner 20 may varydepending on the user and the particular device 10 being utilized.According to one embodiment, inner liner 20 is configured to wickexcessive moisture away from the surface of the residual limb to avoiddiscomfort to the user and/or improper fit of device 10.

According to an exemplary embodiment, an outer casing 22 may be providedwith a size and shape customized to a particular user such that asubstantial portion of a residual limb may be received within theinterior of outer casing 22. As shown in FIG. 2, a cavity 28 may remainafter insertion of the residual limb and inner liner 20 into outercasing 22 and prior to application of a vacuum to socket assembly 12. Asdiscussed below, a desired vacuum can be applied to cavity 28 to providea proper fit between the residual limb and outer casing 22.

According to an exemplary embodiment, sealing sleeve 24 may beconfigured to form an airtight seal between the residual limb and outercasing 22. For example, sealing sleeve 24 may in some embodiments be anon-foamed, nonporous polyurethane suspension sleeve that rolls over andcovers a portion of outer casing 22 and a portion of the residual limb.The inner surface of sealing sleeve 24 may provide a seal against theskin on the user's thigh and the outer surface of the prosthetic socketto provide an airtight seal for the vacuum. Sealing sleeve 24 may beapplied over the outer surface of outer casing 22 and rolled up onto thethigh portion of the residual limb after inner liner 20 is fit properlyto the residual limb, and inner liner 20 and the residual limb arepositioned within outer casing 22. Sealing sleeve 24 can provide avacuum seal to enable device 10 to achieve appropriate vacuum (measuredin, e.g., inches of mercury) and prosthetic suspension.

According to an exemplary embodiment, pylon 14 is attached to socketassembly 12 at an upper portion 30 of pylon 14. According to someembodiments, pylon 14 and socket assembly 12 may be coupled using alocking pin, such that a pin extending from a lower portion of socketassembly 12 is lockably received within a recess, or aperture, withinpylon 14. Any other suitable means may be used to couple socket assembly12 and pylon 14. Lower portion 32 of pylon 14 may be coupled to and/orform a part of artificial foot 16. Any suitable coupling means may beused to couple pylon 14 to artificial foot 16.

According to an exemplary embodiment, artificial foot 16 is configuredto substantially replicate an actual human foot in shape, size, and/orrange of motion. As indicated above, while the embodiments disclosedherein generally refer to a lower limb prosthetic device used inconnection with an artificial foot, the teachings herein extend to otherapplications, including upper limb prosthetics and other devices thatwould benefit from the features disclosed herein. Artificial foot 16 maybe made any suitable material, and the shape, size, and othercharacteristics of artificial foot 16 may be varied from those describedherein to suit a particular user and/or application.

Referring to FIGS. 2-5 and 8-11, according to an exemplary embodiment, aforce sensing member 26 provides a plurality of force sensors 48 thatare distributed over the surface of or within force sensing member 26.Force sensing member 26 detects forces acting upon the residual limb andtransmits signals (e.g., via a wired connection 50 and/or a wirelessconnection via transceiver 46) to controller 34 based on the forcesdetected. While the embodiments herein generally refer to forces andforce sensors, the embodiments are equally applicable to pressuresensors (e.g., sensors that determine forces applied over a certainarea). Force sensors 48 are configured to sense the force experienced bythe residual portion of the limb through inner liner 20. In someembodiments, as shown in FIG. 8, force sensors 48 may be distributedgenerally evenly by providing a matrix of generally evenly spaced forcesensors 48. Alternatively, as shown in FIG. 9, a plurality of forcesensors 48 may be provided that are distributed unevenly at desiredplaces (e.g., locations known to experience significant forces, changesin forces, etc., due to changes in user activity, changes in userposition (e.g., standing versus sitting etc.), changes in a user's paceof walking, jogging, etc., and the like). For example, in areas thatexperience fewer changes in the force applied to the residual limb(e.g., at the lateral sides of the residual limb), fewer force sensorsmay be used, whereas in areas where forces on the residual limb may begreater or subject to larger fluctuations (e.g., on theanterior/posterior walls and the distal end of the residual limb), moreforce sensors may be utilized. The placement, number, density, etc., offorce sensors 48 used in connection with force sensing member 26 may bevaried to suit a particular application, a particular user (e.g.,height, weight, etc.), a type, shape, size, etc. of residual limb, andso on.

In some embodiments, force sensors 48 may be integrated into liner 20 orprovided as part of a separate component from liner 20. For example,each sensor 48 may have a wired connection extending from the forcesensor. Control electronics may be coupled to the liner (or anothercomponent of the socket assembly) to compile the data from the variousforce sensors and then transmit formatted signals to control system 18via wired connection 50. As such, rather than sending a number ofdifferent wires/conductors to control system 18, the number ofindividual conductors may be minimized. According to an alternativeembodiment, the communications between the control electronics coupledto the socket assembly and control system 18 may be wireless. Accordingto another embodiment, a conductive pin lock may be used (e.g., similarto a phono jack) where control signals are provided over the powertransmission.

According to an exemplary embodiment, force sensing member 26 mayinclude a plurality of overlapping strips of material 52, 54, that maybe arranged such that force sensors 48 are defined by the intersectionsof strips 52 and strips 54. For example, referring to FIG. 4, forcesensors 48 are defined by the intersections of strips 52, 54. Accordingto one embodiment, force sensing member 26 may include overlappingstrips of flexible polymer material (e.g., utilizing the ZEBRA Systemavailable from Sensortech Corporation, of Greenville, S.C.). Accordingto various other embodiments, the individual force sensors may beprovided utilizing different materials and or components in connectionwith force sensing member 26 (e.g., Tekscan Flexiforce sensors availablefrom Tekscan, Inc., of South Boston, Mass.). Referring to FIG. 5, forcesensing member 26 may enable users to generate graphical views of theforce distribution over the surface of the residual limb (e.g., viewableon remote terminal 47 or another device). For example, FIG. 5 shows anexemplary embodiment of a graphical depiction 56 showing points 58, 60of increased force/pressure detected upon the residual limb. Asdiscussed in greater detail below, the vacuum within socket assembly 12may in turn be controlled based on these detected forces.

Referring now to FIG. 3, control system 18 is shown in greater detailaccording to an exemplary embodiment. As shown in FIG. 3, control system18 includes a controller 34, a vacuum sensor 36, a vacuum pump 38, othersensors 40, a power supply 42, a transceiver 46, and output device(s)44. According to various alternative embodiments, control system 18 mayinclude more or fewer components than those described herein.Furthermore, while various components are shown as being independentfrom one another, in various alternative embodiments, one or more of thecomponents of control system 18 may be combined, and similarly,individually shown components may be divided further intosub-components.

Referring further to FIG. 3, controller 34 may include a microprocessor,memory, and other electronics components required to control theoperation of the other various components of control system 18 anddevice 10. As discussed in greater detail below, controller 34 may beconfigured to control the operation of various components of device 10(e.g., vacuum pump 38, output device(s) 44, etc.) based on input signalsreceived from other components of device 10 (e.g., force sensing member26, vacuum sensor 36, etc.).

Vacuum Sensor 36 may be configured to detect the pressure, or vacuumlevel, within socket assembly 12 (e.g., within cavity 28) and togenerate signals representing the detected pressure. The signalsgenerated by sensor 36 are provided to controller 34 for furtherprocessing. Any suitable sensor may be utilized, and sensor 36 may bepositioned within housing 19, adjacent socket assembly 12, or at anyother suitable or desirable position.

Vacuum pump 38 is connected to socket assembly 12 via a fluid connection29 that provides fluid communication between pump 38 and cavity 28 ofsocket assembly 12. Any suitable pump may be utilized (e.g., a diaphragmpump driven by a DC motor, etc.). Operation of pump 38 creates thepartial vacuum in cavity 28 that in turn secures the residual limb tosocket assembly 12. As discussed in greater detail below, controller 34may control the operation of pump 38, and therefore the vacuum withincavity 28, based on a number of different factors, or inputs, eitheralone or in combination with each other. Vacuum pump 38 may be locatedwithin housing 19, or at other locations on device 10. For example,according to one embodiment, pump 38 may be provided adjacent the lowerportion of socket assembly 12 and “in-line” with pylon 14 (e.g., suchthat the vacuum pump forms part of the structural support for socketassembly 12). Alternatively, pump 38 may be coupled to an exteriorportion or surface of socket assembly 12.

Other sensors 40 may further be provided as part of control system 18according to various other embodiments. For example, sensors 40 mayinclude a barometric sensor that senses the current barometric pressureand provides corresponding signals to controller 34. Based on thesesignals, controller 34 may calibrate the other sensors (e.g., vacuumsensor 36) based on the current atmospheric pressure such that device 10may accommodate changes in altitude, etc. Sensors 40 may further includean acceleration or orientation sensor that provides signals tocontroller 34 based on the acceleration and/or orientation of device 10.The acceleration or orientation sensor may be configured to detect awide range of parameters, including acceleration, inclination, pitch,yawl, roll, dynamic movement data, static angular data, and so on.According to various other embodiments, additional and/or differentsensors may be utilized in connection with device 10, and controller maytake into account various data received from the sensors individually orin combination. Furthermore, based on the type of sensor and theparticular prosthetic device, the position of the sensors may be variedto ensure that the proper parameters may be accurately detected.

Power supply 42 may be configured to supply the necessary power to thecomponents of control system 18 and/or other components of device 10(e.g., additional sensors, pumps, user interface devices, etc.).According to one embodiment, power supply 42 comprises a battery.According to various alternative embodiments, the battery may be arechargeable, replaceable, and/or removeable battery. Any suitablebattery may be used, including a lithium-ion battery, a lithium polymerbatter, etc. For example, in one embodiment, the battery is a 3.7 Voltlithium ion battery. In some embodiments, power supply 42 may furtherinclude an interface (e.g., an electrical plug/socket) configured toreceived power from an external power supply (e.g., to recharge one ormore batteries, to provide power during clinical evaluations, etc.).

Output device 44 may include a wide variety of different output devicesconfigured to provide different types of outputs to users. For example,output device 44 may include visual output devices (e.g., lights, etc.),audible output devices (e.g., beepers, buzzers, etc.) and/or tactileoutput devices (e.g., vibratory devices, etc.). Output devices 44 may becontrolled by controller 34 and may be activated based on a variety ofcriteria, including inputs from force sensing member 26 (e.g.,indicating excessive force measurements), vacuum sensor 36 (e.g.,indicating an improper vacuum level or potential problems with socketassembly 12), power supply 42 (e.g., indicating a low power level forone or more batteries), etc. Other types of output devices may be usedaccording to various other embodiments, and the output devices may beactivated based on a number of additional inputs beyond those describedherein. Further, any conventional output devices may be utilized, andthe output devices may be positioned at any suitable location on device10.

Transceiver 46 may be a wireless transceiver configured to establishwireless communications with a remote terminal 47 or other device.Transceiver 46 may be configured to communicate using a variety ofcommunication protocols (e.g., Bluetooth communications, infraredcommunications, 802.11x (e.g., Wi-Fi) communications, cellularcommunications, etc.) and with a wide variety of remote terminals 47(e.g., personal digital assistants (PDAs), laptop computers, desktopcomputers, server computers, etc.). Furthermore, in some embodiments,remote terminal 47 may be a terminal usable by a user of device 10(e.g., such that a user may provide inputs to and/or receive outputsfrom control system 18 while the user is wearing device 10). Forexample, terminal 47 may be a wearable device configured to be wearableon a belt of a user, worn on the wrist of a user, etc. Alternatively,remote terminal 47 may be a computer used by a clinician or physician ina clinical setting to evaluate, calibrate, modify, etc. device 10.

It should be understood that device 10 may include additional componentsto those described herein that may be used in the operation of device10. For example, one or more valves (e.g., a check valve, solenoidvalve, etc.) may be provided in line with fluid connection 29 betweenvacuum pump 38 and socket assembly 12 such that air/fluid is permittedonly to exit socket assembly 12 via fluid connection 29. Othercomponents may be added according to various other embodiments asunderstood by those skilled in the art.

Referring now to FIG. 6, a block diagram of a method of controlling thevacuum level for device 10 is shown according to an exemplaryembodiment. First, a residual limb is secured to a socket assembly (step62). For example, as discussed in detail herein, a user may first applyan inner liner to a residual limb, and then insert the residual limb andinner liner into an outer casing. Next, the residual limb is secured tothe socket assembly through application of a vacuum to the void createdbetween the residual limb and the outer casing (step 64). According tovarious exemplary embodiments, the initial vacuum level maybe preset bythe user and/or a clinician. According to other embodiments, the initialvacuum level may be determined by controller 34 based on any of a numberof inputs from the various sensors disclosed herein. Next forces aredetected at various locations about the residual limb by force sensingmember 26 (step 66) and corresponding signals are provided from forcesensing member 26 to controller 34. Controller 34 then determines alikely user activity (e.g., mode of ambulation, activity such asdriving, sitting, standing, etc.) and/or an orientation of device 10based on the signals received from force sensing member 26 (step 68).Based on the signals received from force sensing device 26 and/or thedetermined activity/orientation, controller 34 then controls vacuum pump38 accordingly (step 70). For example, controlling pump 38 may includeactivating/deactivating pump 38, increasing/decreasing the rate ofoperation of pump 38, etc. Steps 66-70 may then be repeated on acontinuous, intermittent, or other basis to maintain the vacuum levelwithin socket assembly 12 at a proper level.

Referring now to FIG. 7, a block diagram of a method of controlling thevacuum level for device 10 is shown according to another exemplaryembodiment. The method illustrated in FIG. 7 is in many aspects similarto the method illustrated in FIG. 6. However, according to an exemplaryembodiment, the method illustrated in FIG. 7 provides the additionalfeature of detecting forces and controlling vacuum levels on a morelocalized basis (e.g., such that forces may be detected, and the vacuumcontrolled, for different localized regions of socket assembly 12).

First, a residual limb is secured to a socket assembly (step 72). Next,the residual limb is secured to the socket assembly through applicationof a vacuum to the void created between the residual limb and the outercasing (step 74). Next forces are detected at various locations aboutthe residual limb by force sensing member 26 (step 76) and correspondingsignals are provided from force sensing member 26 to controller 34.Controller 34 then determines a likely user activity (e.g., mode ofambulation, activity such as driving, sitting, standing, etc.) and/or anorientation of device 10 based on the signals received from forcesensing member 26 (step 78). Based on the signals received from forcesensing device 26 and/or the determined activity/orientation, controller34 then controls vacuum pump 38 accordingly (step 80). As indicatedabove, the vacuum level within socket assembly 12 may be controlled on alocalized basis based on the various forces detected by force sensingmember 26. For example, a portion of the residual limb may be dividedinto a number of localized regions, and force sensor 26 may beconfigured to detect at least one force for each localized region.Controller 34 may then in turn control the vacuum level (e.g., controlpump 38 so as to maintain, increase, or decrease a vacuum level in aparticular localized region) in each localized region based on theforces being experienced by that specific region. For example,controlling pump 38 may include activating/deactivating pump 38,increasing/decreasing the rate of operation of pump 38, etc. Steps 76-80may then be repeated on a continuous, intermittent, or other basis tomaintain the vacuum level within socket assembly 12 at a proper level.

An exemplary embodiment of a portion of a socket assembly that mayprovide for localized control of vacuum with the socket assembly isshown in FIGS. 10-11. As shown in FIGS. 10-11, in order to provide forlocalized control of vacuum, a manifold 25 may be provided within outercasing 22 and may define a number of regions 21, each region 21 beingdefined by a number of dividers 27. According to one embodiment,dividers 27 are provided on an inner surface of manifold 25 (e.g., bydebossing the inner surface of manifold 25) such that dividers 27 formlocalized regions 21 that can each have different vacuum levels. Asshown in FIG. 11, the localized regions 21 may in turn all be in fluidcommunication via an intermediate space 23. For example, in oneembodiment, each region 21 may be in fluid communication withintermediate space 23 by way of a valve 31 (e.g., a check valve, etc.).Each valve 31 may control fluid communication between intermediate space23 and each localized region 21, such that by controlling whether aparticular valve 31 is open or closed, a vacuum applied to intermediatespace 23 (e.g., via fluid connection 29) may in turn be selectivelyapplied to the localized region 21. In this way, the vacuum appliedacross the surface of the residual limb may be varied in response to theforces acting upon the residual limb. As shown in FIG. 11, each valve 31may be controlled via a control line 33, or alternatively, via anothertype of wired or wireless connection.

According to some embodiments, in order to ensure proper sealing forlocalized regions 21, inner liner 20 may be customized to conform tomanifold 25. For example, inner liner may include raised portions (e.g.,detents, etc.) that are configured to align with or otherwise provide acomplimentary fit with corresponding structure (e.g., dividers 27) onmanifold 25. In other embodiments, portions of inner liner 20 may beconfigured to fit within debossed portions of manifold 25. In this way,both a vacuum and mechanical “lock” is formed between the socketassembly (e.g., each localized region 21) and the residual limb.

According to an alternative embodiment, rather than manifold 25 beingprovided to the interior of outer casing 22, a manifold may be coupled,for example, to the outer surface of outer casing 22 such that eachlocalized region 21 has a fluid connection to the manifold, and themanifold controls distribution of the vacuum from fluid connection 29 toeach localized region 21. Other types and arrangements of manifolds maybe used according to various alternative embodiments. For example, themanifold may be integrated with the vacuum pump such that fluidcommunications to each localized region are provided from the vacuumpump.

According to an exemplary embodiment, each localized region 21 isassociated with a single force sensor 48. According to otherembodiments, each localized region 21 may be associated with a pluralityof force sensors 48. Further, the force sensor(s) provided within eachlocalized region 21 may be distributed evenly within the localizedregion, or unevenly distributed at desired locations.

According to various embodiments, controller 34 may be configured suchthat the vacuum level within cavity 28 may be controlled independentfrom inputs received from vacuum sensor 36 (e.g., in connection with oneor both of the methods illustrated in FIGS. 6-7). In other words, theactual vacuum level may be controlled based on the forces detected byforce sensing member 26, rather than vacuum sensor 36. In alternativeembodiments, controller 34 may control vacuum pump 38 based on inputsreceived from force sensing member 26 in combination with inputsreceived from vacuum sensor 36 and/or any other sensors 40. Furthermore,controller 34 may be configured to provide control signals to forcesensing member 26 such that the force detection method may be adjustedto vary the frequency or pattern at which force sensors 48 detectforces/pressures applied to the residual limb. For example, based on avariety of factors (e.g., force measurements, a determined userorientation/activity/mode of ambulation, etc.) the rate at which forcesensors detect forces may be adjusted accordingly. In one embodiment,controller 34 may be configured to provide a “sleep” mode such that therate at which forces are detected and/or signals are sent to controller34 is significantly reduced, which in turn conserves power for device10. This type of control may be via signals provided directly to forcesensors 48, or may be via signals sent to control electronics coupled toinner liner 20 that in turn control the operation of force sensors 48.

According to yet further embodiments, controller 34 may be configured tocontrol the operation of pump 38 based on signals received over a periodof time from one or more sensors (e.g., force sensors 48, vacuum sensor36, other sensors 40, etc.). For example, based on changes in force overa period of time, controller 34 may determine a likely mode ofambulation (walking, jogging, running, etc.), whether a user isgenerally standing still or moving, whether a user is sitting, standing,etc., and the like. Various algorithms may be utilized in taking intoaccount changes in force over time, and controller 34 may be configuredto make other determinations than those described herein. According tovarious other embodiments, controller 34 may be configured to receivesignals corresponding to specific movements of a user (e.g., a series ofquick downward pressures, or a similar pattern that may not normallyoccur during normal use of device 10) and to trigger a specific mode(e.g., a predefined mode, a user/clinician defined mode, etc.) ofoperation for device 10 (e.g., a sleep mode, a low vacuum level mode,etc.). Controller 34 may be further configured to return to normaloperation in response to yet other signal types (e.g., signalscorresponding to a sudden increase in experienced forces due to a userstanding up, etc.).

In some embodiments, shielding may be incorporated into the prostheticdevice to protect the system components and minimize interference to thevarious signals being transmitted. For example, an shield member (e.g.,an at least partially conductive member) may provide protection fromelectrostatic discharge (ESD) and minimize radio frequency interference(RFI), electromagnetic interference (EMI), and/or other interferencethat may be created by operation of the various force sensors and othercomponents of the prosthetic device.

It should be understood that as used herein, the term “applying avacuum” and similar terms generally refer to operating a vacuum pump influid communication with a cavity so as to generate a partial vacuum(e.g., a space of reduced gas pressure) within the cavity. The partialvacuum in turn creates a suction force that is applied to a residuallimb and a socket assembly to maintain a proper fit between thecomponents.

The prosthetic device shown in the various embodiments illustratedherein may provide benefits over more traditional prosthetic devices.For example, because vacuum levels may be controlled based on forcemeasurements, the prosthetic device is able to automatically accommodatechanges in atmospheric pressure by increasing/decreasing the amount ofvacuum applied in response to changes in forces detected. As such, issome embodiments the use of a separate barometric pressure sensor may beunnecessary. Furthermore, the force sensors may be positioned in anydesired location, and the locations may be customized to a particularuser of a prosthetic device by a user and/or a clinician. Further yet,the prosthetic device may be configured such that after an initialconfiguration/calibration of the prosthetic device (e.g., the controlsystem and associated components), the prosthetic device automaticallymaintains specific desired levels of socket pressure based on useractivity or other factors, without the need for any input fromusers/clinicians or any additional user interfaces, etc. Additionally,the prosthetic device may be configured to detect “milking” or“pistoning” of the distal end of the residual limb (e.g., based onforces detected over a period of time) and automatically adjust thevacuum applied to the socket assembly to minimize these conditions.

It is important to note that the construction and arrangement of theelements of the prosthetic device as shown in the exemplary embodimentsare illustrative only. Although only a few embodiments have beendescribed in detail in this disclosure, those skilled in the art whoreview this disclosure will readily appreciate that many modificationsare possible (e.g., variations in sizes, dimensions, structures, shapesand proportions of the various elements, values of parameters, mountingarrangements, materials, colors, orientations, etc.) without materiallydeparting from the novel teachings and advantages of the subject matterrecited in the embodiments. For example, for purposes of thisdisclosure, the term “coupled” shall mean the joining of two membersdirectly or indirectly to one another. Such joining may be stationary innature or movable in nature. Such joining may be achieved with the twomembers or the two members and any additional intermediate members beingintegrally formed as a single unitary body with one another or with thetwo members or the two members and any additional intermediate memberbeing attached to one another. Such joining may be permanent in natureor alternatively may be removable or releasable in nature. Such joiningmay also relate to mechanical, fluid, or electrical relationship betweenthe two components. Accordingly, all such modifications are intended tobe included within the scope of the present disclosure as defined in theappended claims. The order or sequence of any process or method stepsmay be varied or re-sequenced according to alternative embodiments.Other substitutions, modifications, changes, and/or omissions may bemade in the design, operating conditions, and arrangement of theexemplary embodiments without departing from the spirit of the presentdisclosure.

What is claimed is:
 1. A method of controlling an amount of vacuum to acavity of a prosthetic limb, the method comprising: applying the amountof vacuum to the cavity defined by a socket of the prosthetic limb and aportion of a residual limb of a user, the portion of the residual limbreceived within the socket, wherein the cavity includes a plurality oflocalized regions defined by dividers embossed in a manifold of an outercasing of the prosthetic device, wherein the manifold includes aplurality of control valves, wherein each control valve of the pluralityof control valves is associated with a different localized region;detecting forces experienced by the residual limb at a plurality oflocations about the portion of the residual limb during use of theprosthetic device by the user using a plurality of force sensors,wherein the plurality of force sensors are distributed unevenly suchthat there are fewer force sensors positioned near lateral sides of theresidual limb than positioned near an anterior side and a posterior sideof the residual limb; providing signals to a controller based on theforces detected at the plurality of locations; and controlling theamount of vacuum applied to the cavity based on the signals byselectively opening and closing the each of the control valves of theplurality of control valves such that vacuum applied across a surface ofthe residual limb is varied by localized region.
 2. The method of claim1, wherein the amount of vacuum applied to the cavity is controlledindependent from a detected vacuum level within the cavity as detectedby a vacuum sensor.
 3. The method of claim 1, further comprisingdetermining an activity of a user based at least in part on the signalsand controlling the amount of vacuum based on the determined activity,wherein the activity comprises one of standing, sitting, and walking. 4.The method of claim 1, further comprising determining an orientation ofthe prosthetic device based on the signals.
 5. The method of claim 1,further comprising determining a mode of ambulation based on thesignals.
 6. The method of claim 1, wherein the controller isconfigurable to control the amount of vacuum applied to the cavity basedonly on the signals.
 7. A method comprising: detecting forcesexperienced by a residual limb at a plurality of locations about aportion of the residual limb during use of a prosthetic device using aplurality of force sensors, each force sensor located adjacent one ofthe plurality of locations, wherein the plurality of force sensors arearranged in a matrix; providing signals to a controller based on theforces detected at the plurality of locations; and selectivelycontrolling an amount of vacuum applied to each of a plurality oflocalized regions on the residual limb based on the signal, wherein eachof the localized regions is defined by dividers embossed in a manifoldof an outer casing of the prosthetic device, wherein the manifoldincludes a plurality of control valves, wherein each control valve ofthe plurality of control valves is associated with a different localizedregion, wherein selectively controlling the amount of vacuum applied toeach of the plurality of localized regions includes selectively openingand closing the each of the control valves of the plurality of controlvalves such that vacuum applied across a surface of the residual limbmay be varied by localized region.
 8. The method of claim 7, furthercomprising: selectively controlling the amount of vacuum applied to eachof the plurality of localized regions independent from a measured vacuumlevel within each localized region.
 9. The method of claim 7, whereinthe prosthetic device comprises a socket assembly having a manifoldconfigured to selectively control the amount of vacuum provided from avacuum pump to each localized region.
 10. The method of claim 7, whereineach localized region is associated with at least one force sensor.